Method and machine for making tubular rivets and the like



o. L. SMITH 1;830,722 v METHOD AND MACHiNE FOR MAKING TUBULAR RIVETS AND THE LIKE Nov. 3, 1931.

5 sheets-sheet 1 v Filed March 16. 1931; v

NOV. 3,,193I.- O sM A 1,830,722

METHOD AND MACHINE FOR MAKING TUBULAR RIVETS AND THE LIKE Filed March 16, 1931 5 Sheets-Sheet V 2 Nov. 3, 1931. o. L. SMITH I 1,830,722

METHOD AND MACHINE FOR MAKING TUBULAR RIVETS AND THE LIKE Filed March 16, 1931 5 Sheets-Sheet 5 Patented N56. 3, 1931 UNITED STATES PATENT OFFICE oscAa L. SMITH, or TOMS Riven, NEW JERSEY ME'r Hon AND MACHINE non. MAKING TUBULAR nIvErs AND'THE LIKE Application filed March 16, 1931. Serial No. 523,109.

' distinct from prior methods involving an actual removal of a portion of said stock by a drilling or like operation, and a principal object of the invention is to provide a practicable and efficient method and mechanism w of the stated character materially simplifymg and facilitating the manufacture of articles of this type.

More particularly the invention has for an object the provision of an improved method and machine for manufacturing tubular ended rivets, and for the purpose of illustrating the invention'I have herein described, and showin the attached drawings, a machine adapted for this function.

In the/drawings? t Figure 1 is a side elevation, partial sectional view of the machine; I

Fig. 2 is a plan and partial sectional view of the machine; I I r Fig. 3 is a; section on the line 3--3, Fig. 2';

Fig. 4 is a fragmentary side elevation, il-' lustrating a detail of the mechanism;

Figs. 5-to 8, inclusive, are fragmentary sec-' tional 'views'illustrating various steps in the manufacture of the rivet;

,Figs. 9 to 1l,inclusive, are slmllar sectional views illustrating a modification of a the process; and I Figs. 12 to' 15, inclusive, are similar sectional views illustrating a still further mod1- fiziation in the process of manufacture, also W thin the scope of my invention.

It has been customary, in the manufacture of tubular rivets to form the tubular ends by drilling, an operation complicating and retarding the manufacturing rocess and adding materially'to its cost. y the present invention, I have provided a practicable method whereby the tubular formation may 4 be effected by a displacement of the metal of the rivet blank in an operation analogous to extrusion, and thereby materially facilitate and reduce the cost of manufacturing rivets of this type.

tion, of high periodicity and prefera In practicing the invention in accordance with a preferred procedure Iemploy a die having a cylindrical bore neatly receiving the shank of the rivet blank together with a tool which enters the said bore and is forcibly engaged'with the end of the shank, pressurebeing applied to relatively advance the tool and the said blank and to cause the end portlon of the tool, which is somewhat smaller cross sectionally than the die bore, to penetrate the end of the shank; The metal thus displaced by the tool necessarily-flows longitudinally of the bore around the vpenetrating end of the tool to form the tubular end of the finished rivet. During the relative. advance movement of the tool and blank, one or both are "given a longitudinal reciprocal of small throw, effecting a series of rapid im-, pingementswhich not only materially facili tates the displacement operation by causing an incremental'fiow of the metal but also relieves a part of the heavy strain to which .the toolis subjected and avoids the development of excessive temperatures which would tend jointly. to cause rapid deterioration of the tool. This longitudinal relative vibration of the tool and the rivet blank also prevents adhesion of the displaced metal to the tool and simplifiesthe subsequent stripping operation in which the rivet is separated so from the tool. Simultaneously with aforedes'cribed operations the tool and the rivet blank are preferably relatively oscillated or rotated about their jointlongitudinal axis which still further facilitates the displacement'operation and permits the use of tools of various favorable shapes other than-cylindrical in the formation of a truly cylindrical recess-in the tubular end of, the rivet.

In the drawings, the reference numeral l designates the bed plate of a rivet-forming machine made in accordance with my inven tion. The machine further comprises a die} head 2 relatively fixed on the bed plate, and a head-stock 3 slidably mounted on the bed plate for reciprocation relative to the die head. As illustrated in Fig. 5, the die head 2 is provided with a recess for reception of a die 4, the latter having a cylindrical bore 4aformed to receive the correspondingly 100 formed shank 5 of a rivet blank, and said head is channeled at 6 in alignment with the die aperture, for passage of a shaft 7 ,having at its end a. socket for reception of a suitable working tool 8 which as illustrated enters the inner end of the bore 4a. a The shaft 7 extends rearwardly, through rectangular member 9 Whichis slidably mounted in a corresponding- 1y formed passage in the superstructure of a carriage 11, this carriage being slidably supported and guided in a recessed-portion 12 ofthe bed plate 1. That. portion of the carriage 11 which receives the member 9 is chambered at 14 for reception of a cross-head 15, this cross-head having, an opening adapted to receive a cylindrical pin 16 projecting from one side ofthe rectangular member 9. The cross-head is also provided with a second cylindrical opening for reception of themcentric cylindricalextension 17 of a shaft 18,

the latter being journaled in bearings 13 in the carriage 11 (see Fig. 2) at right angles to the axis of the shaft 7 and of the member 9. The shaft 18 carries a fiy-wheel 19 and a pulley '21, which is connectedthrough the medium of a belt 22 to a pulley 23 on the shaft A sh eave 27 is locked on the shaft between I the nut 26' and a second nut 28, this sheave being connected through a belt 29 with a pulley 31 on the motor shaft 32, the said belt extending around idler pulleys 33 and 34 onthe bed plate 1. Rotation of the sheave 27 from the mbtor 24 results in a rotation of the shaft 7, and simultaneously with the rapid reciprocation or longitudinal vibration of the the said shaft 18 and the associated mecha: nism. 7 x

' Pivotally secured at 35 to the bed plate 1 is a lever 36, this lever. carrying a stud 37, the head of which engages aside of the carriage 11. The outer end ofthe lever 36 is engaged by a rod "38, which extends longitudinally of i the bed plate and is'attached at its outer end to a lever 3-9 pivotally secured at 41 to the bed plate 1 or to a similar relatively fixed part of the machine. The lever 39 carries a roller 42, which is in operative engagement with a cam .43 on a shaft This shaft may also carry a crank mechanism (not shown) for operative connection with thehead-stock 3,

through the medium of which said head-stock is moved toward and from the die head 2, as hereinafter set forth. Longitudinal move shaft effected as previously set forth through a consequent reciprocation of the carriage 11, springs 45 being provided, confined between the carriage 11 and a portion of the bed plate In Figs. 5 to.8, inclusive, are illustrated the various steps in the manufacture of a tubular-ended rivet 1n accordance with my invention. The cylindrical rivet stock, having been headed in a previous operation, is transferred to the die 4 as illustrated in Fig. -5, the head-stock 3 being advanced to. retain the rivet securely in the dieduring subsequent operations. the shaft 7 with-the tool 8 into engagement with the inner endof the'rivet Sha-Ill ,th8 said tool being continuously vibrated and simultaneously rotated as previously set forth. The tool, by reason of its forward movement, coupled with the rapid vibration The cam 43 now acts to advance f and rotational movement, forces itself inlo .the body of the rivet, the metal displacedby the tool entering the space surrounding the operatin end of the i001, as illustrated in 'Flg; 6.

hen the metal has solidly engaged the shoulder 46 of the tool, the head-stock 3.

*is withdrawn and the continued forward movement of the shaft 7 forces the rive; out wardly from the die. In general, the vibratory movement of' the tool is su'f ficient to clear the rivet from the end xhereof, although I may provide, in addition, a 5

stripper finger 47 (see Figs. 7 and 8), which functions to insure a separation of the rivet from the end of the tool, as shown in the lastnamed figure." I

. In the modified process illustrated in Figs.

9 toll, the rivet stock 49 is entered in the die'intocontact with the vibratingand rotating tool 8 by the head-stock 3, Which in a continuedadvancement following engagement of-thestock with the tool, forms the rivet head in the usual manner simultaneously with the formation by thetool 8 and in the manner previouslyset forth of the recess in the inner end of the rivet. In this in stance, the rivet may be ejected from the die 5 and strippedfrom the tool in the manner prevlously described.

I have found it-desirable to make the ad'- vance of the tool during the initial and major portions of the displacing operation, relatively rapid, and to feed the tool at a greatly reduced rate during-the latter portion of the operation, and in Fig. 4, I have'illusment of the rod 38, by theaction of the cam trated a cam adapted forthis function. In

43,- effects an oscillation of the lever 36 and actual operation of my machine in manufacturing' small rivets, cation of the tool of ill r a working tool, and forcibly relatively feed- (in I'have found a reciprothree thousand R. P. M. and a" rotation of 490 R. P. M. highly satisfactory. An excesslvely rapid reciprocation is difiicult to control mechanically, and too rapid rotation tends to burn the tool or the stock,but within the limits imposed by such considerations, a wide range of speeds varying either way from those specifically mentioned will be found entirely practicable.

In the modification illustrated in Figs. 12, to 15, the die is provided with a cavity 51, which receives the inner end of the rivet blank upon which preferably the head has previously been formed. In this instance, the tool 8 advances as described above into engagement with the inner end of the blank, the effect of the reciprocatory tool action being to upset the end of the shank into the cavity 51, as illustrated in Fig. 13. Subsequently, the head 3 is retracted, to permit a continued advance movement of the tool 8 to force the rivet outwardly from the die. This outward movement causes a drawing of the metal of the upset end portion of the .rivet around'the working head of the tool,

as illustrated in Fig. 14, thus completing the formation of thetu'bular recess, the finished rivet being ejected in the manner previously described and as illustrated in Fig. 15. The

vibra'tory'movement of the tool materially. aids the formation of the rivet by this method.

The mechanism described above is extremely rapid in operation and possesses a capacity' far exceeding that of the machines ofthe prior practice. The machine is also substantially free from the disadvantages usually encountered in a rapid displacement of metal by an extruding ,process, such for example as frequent failure of the" tool and inequalities inthe product. Although preferring to use the'si'multaneous reciprocatory and r0 tary action, as described, the invention may be practiced to advantage with reciprocation alone. While finding a useful application in the manufacture of tubular rivets, the 'invention in principle may be applied to ad vantage to the manufacture of many other articles'su'ch for example as socketed set-- screws, cartridge shells and many other. forms of hollow or recessed products. It will also be apparent that mechanism by which the invention may be practiced may vary widely as to form andmode of operation.

I claim: i g

1. The method which comprises confining a metallic body in a die in engagement with ing said tool and body together simultane ously with a r pid relative reciprocation thereof to thereby effect a-displacement of the metal of .the body by -molecular flow around the tool.

2. The method which comprises confining a metallic body in a die in engagement with a working tool, forcibly relatively feeding said tool and body together, and simultaneously relatively reciprocating and'rotating H said tool and body to effect a displacement of the metal of the body by molecular flow die relatively moved with respect to the body, and simultaneously with said drawing operation relatively reciprocating .saidtool and said body.

drawing. the upset portion of said metallici loodyl around the sides of said tool by means. of a 4. The method which comprises relatively i feeding a metallic body and a tool toward.

each other to upset that end of the body e11 gaged by the tool, subsequently'drawing the upset tion relatively reciprocating and rotating said tool and body.

portion of said metallic body around the sides of said tool by means of'a die relatively moved with respect to the body,

and simultaneously with the drawing opera-1 5. The method which comprises confining a metallic'body in a die with a portion thereof projecting, forcibly relatively feeding a tool and said body together to upset the projecting portion, thereafter relatively moving the die and said tool to cause the latter to force the upset portion of said body into the die to efiect a drawing of said upset metal around the sides of the tool, and simultane-- ously relatively reciprocating said tool and bodv.

- 6. The method which comprises confining a metallic body in a die with a portion thereof projecting, forcibly relatively feeding a tooland'said body together to upset the. projecting portion, thereafter relatively moving the die and said tool to cause the latter to force the upset portion of said body into the die to effect a drawing of said upset metal around the sides of the tool, and simultane-' ously relatively"reciprocating and rotating said tool and body.

7 The method which comprises confining a metallic body in a die in engagement with a workingtool, advancing the tool in engagement with the body,

of the tool to effect a the tool. v v

. 8. The method which comprises confining .a' metallic body in a die-in engagement with 9. The methodofforming a' tubular rivet, I

I and simultaneously eifectingya rapid longitudinal reciprocation displacement of the.

metal of the body molecular flow around which comprises inserting the blank shank of said rivet in a cylindrical die opening, in-

' tive reciprocation thereof to thereby effect a displacement of the metal of said shank by a progressive incremental flow into and to fill the annular space between the die opening and the path of said tool.

10. The method of forming a tubular rivet,

which comprises inserting the blank shank of said rivet in a cylindrical die opening, in-

serting in said die opening in engagement with the end of said shank a tool of lesser cross sectional'areathan the die opening,

and forcibly relatively feeding said tool and shank together simultaneously with a relative reciprocation and rotation thereof to effect a displacement of the metal of the body by a progressive incremental flow into and to fill the annular space between the die opening and the path of said tool. 7

11. The method of forming a tubular rivet, which consists in inserting a cylindrical blank in a die with one end projecting, simultaneously engaging the outer projecting end and the inner end of said blank with a heading tool and a forming tool respectively, and feeding said tools toward each other simultaneously with a rapid reciprocation of said forming tool to simultaneously head the rivet and to effect a displacement of the metal of the inner end of said blank by molecular flow around said forming tool.

12. The combination with a die having an opening adapted for reception of a metallic body, of a tool adapted for insertion in said opening to engage an end of said body, means for relatively feeding said body and tool, and means for simultaneously relatively rapidly reciprocating said tool and body to effect a displacement of the metal of the body by molecular flow around the tool.

13. The combination with a die having an opening for reception of a metallic body, of a tool adapted for insertion in said opening into engagement with said body, means for feeding said tool toward the body, and means for simultaneously rapidly reciprocating said tool to effect a predetermined displacement of the metal of said body within the die.

' 14; The combination with a die having an opening for reception of a metallic body,

of a tool adaptedfor insertion in said opening into engagement with said body, means for feeding said tool toward the body, and means for simultaneously rapidly reciprocating and rotating said tool during the feeding operation.

15. The combination with a die having a cylindrical passage adapted-for reception of a correspondingly formedfme'tallic blank, of

means movable with-respect to the die for confining the blank to said passage at one end of the latter, a tool adapted for insertion into said passage to engage the inner end of said blank, means for jrelatively feeding said blank and tool together, and means for relatively rapidly reciprocating said tool and blank during the feeding operation to cause the metal of the blank to have a progressive incremental flow into and to fill the annular space between the said cylindrical passage and the path of the tool.

1 6. The combination with a die having a cyllndrical passage therethrough adapted for reception of a correspondingly formed metallic blank, of means for closing one end of said-passage to confine the said blank, a tool adapted for insertion in the opposite end of said passage into engagement with said blank, said tool having a working tip of lesser cross sectional size than the said passage, and means for relatively feeding said blank and tool together and for simultaneously relatively reciprocating said tool and blank to effect a displacement of the'metal of said-blank by a progressive incremental flow into and to fill the annular space between the said cylindrical passage and the path of the tip of the tool.

the die opening and the path of the tip of the tool.

18. The combination with a die having an opening adapted for reception of a metallic body, of a tool adapted for insertion in said opening and having a working tip of lesser cross sectional area than said opening, means for forcibly advancing said tool against the said body while confined in said opening, and means for rapidly reciprocating and rotating said tool simultaneously with the advancing operation to causethe metal of the body to have a progressive incremental flow-into and to fill the annular space between the die opening and the path of the tip of the tool.

19'. The combination with a die having a cylindrical passage therethrough adapted for reception of a correspondingly formed metallic blank, of a heading tool for engagement with a projecting end of said blank, a penetrating tool adapted for insertion in said die passage into engagement with the inner end of said blank, means for feeding the said tools simultaneously against the opposite ends of said blank, and means for rapidly rethe metal of the blank to have a progressive incremental flow intoand to fill the annular space between the said cylindrical passage and the path of the penetrating tool.

20. The combination with a die having a cylindrical passage therethrough. adapted for reception of a correspondingly form-ed metallic blank, of a heading tool for engagement with aprojecting end of said blank, apenetrating tool adapted for insertion in said die passage into engagement with the inner end of said blank. means for feeding the'said tools simultaneously against the opposite'ends'of said blank, and means for rapidly reciprocating and rotating said penetrating tool simultaneously with the feeding operations to cause the metal of the blank to have a progressive incremental flow into and to fill the annular space between the said rcylindrical passage and the path of the penetrating tool.-'

21. The combination with a die having a cylindrical passage formed with anintermediate enlargement, said die being adapted to receive in one end a blank rivet having the end of its shank projecting into the enlarged portion of said passage, of a tool adapted for insertion intothe opposite end of said passage in engagement with the end of said shank, means for feeding the tool against the blank to upset theinner end portion of'said blank and to subsequentlyforce the blank' outwardly from sai-ddie passage, means forrapidly, reciprocating said. tool simultaneously with the feeding operations", and means for-confining the blank in the die during the upsetting operation. I

- 22. The me hodwhich comprises confining a metallic body in a'die in engagement with a working tool, and forcibly relatively feeding said tool and the confined body together, simultaneously with a rapid relative reciprocation thereof, thereby to effect a displacement of the metal of the body by. a progressive incremental flow into and to fill the annular. space between the die wall and the path ofthe tool. 23. The method which comprises confining a, metallic body in a die in engagement x with a working tool, forcibly relatively feeding said tool and the confined body together and simultaneously relatively reciprocating and rotating said tool and body to efi'ect a displacement of the metal of the body by a ment of the metal of the body by a progressive incremental flow into and to fill the annular space between the die wall and the path of the tool.

25.- The method which comprises confining a metallic body in a die in engagement with a working tool, advancing the tool in engagement with the confined body, and simultaneosuly reciprocating and rotating said tool to effect a displacement of the metal of the body bv a progressive incremental flow into and to fill the annular space between the die wall and the path ofthe tool.

26. The combination with a die having an opening adapted for reception of a 'metallic body, of a tool adapted for insertion in said opening to engage an end of said body, means for relatively feeding said body confined insaid opening and said tool, and means for simultaneously relatively rapidly reciprocating said tool and confinedbody to efl'ect a displacement of the metal of the body by a progressive incremental. flow into and .to fill the annular space between the die wall and the path of the tool, Y.

27. The combination with a diehaving an opening for reception o'f ametallic body, of

path of the tool. A J

28. The combination with a die having an opening for reception of a metallic body, of a'tool adapted for insertion in said opening into engagement with said body confined by ,1

said opening, means for feeding said tool toward the b 0dy, and means for simultaneous'lyrapidly reciprocating and rotating said tool during thefeeding operation to etfecta displacement of the metal of the body by a progressive incremenal flow into and to fill the ion

the annular space between the die-wall and the path of the tool. L y y OSCARL. SMITH. v

progressive incremental flow into and to fill the annular space between the the path of the tool.

24. The method .which comprises confining a metallic body'in adie in engagement with a working tool, advancing the tool in engagement with the confined body, and

simultaneously efi'ecting a rapid longitudinal reciprocation of the tool to effect a. displacedie wall and 

